544results about How to "Improve flight performance" patented technology

A two-piece solid golf ball has good shot feel, excellent flight performance and durability. The JIS-C hardness of core is A, core inward JIS-C hardness at 5 mm inward from the core surface is B, JIS-C surface hardness of the core is C, cover JIS-C hardness is D, distance in mm between center of core and point 5 mm inward from surface of core is K and radius of ball is L, the golf ball satisfies relations: 65<=A<=69, 83<=B<=87, C is lower than B by 1 to 5, and 1.2<=[)D-B)/(L-K)]/[(B-A)/K]<=2.5; and when deformation amount of core at initial load of 10 kgf to final load of 130 kgf is a, and deformation of golf ball when applying initial load of 10 kgf to final load of 130 kgf is b, the deformation difference (a-b) is 0.5 to 0.9.

The present invention provides a four-piece solid golf ball having excellent flight performance and good shot feel at the time of hitting. The present invention relates to a four-piece solid golf ball comprising a core, an intermediate layer formed on the core, an outer layer formed on the intermediate layer and a cover covering the outer layer, wherein the core has a surface hardness in JIS-C hardness of 67 to 85, a JIS-C hardness of the intermediate layer is higher than the surface hardness of the core, and a JIS-C hardness of the outer layer is higher than the hardness of the intermediate layer.

The solid golf ball of the invention is a one-piece golf ball or a multi-piece golf ball having a solid core enclosed directly in a cover or with an intermediate layer disposed therebetween. The one-piece golf ball or the solid core and/or intermediate layer of the multi-piece golf ball is formed of a rubber composition comprising a base rubber, an unsaturated carboxylic acid or a metal salt thereof, and a sulfur halide. Owing to the optimal degree of deformation and high resiliency of the elastic rubber portion therein, the solid golf ball has an excellent feel and an excellent flight performance.

The present disclosure provides a fuselage of an unmanned aerial vehicle. The fuselage comprises an upper plate, a lower plate opposite to the upper plate, a connecting plate, and a middle spacing plate; the connecting plate is connected between the upper plate and the lower plate; the upper plate, the lower plate, and the connecting plate are enclosed to define a receiving space; the upper plate, the lower plate, the connecting plate, and the middle spacing plate are integrally formed; the upper cavity is located between the middle spacing plate and the upper plate, and the lower cavity is located between the middle spacing plate and the lower plate; and a first mounting opening is defined in the upper plate allowing a component to enter the upper cavity, and a second mounting opening is defined in the lower plate allowing a component to enter the lower cavity.

A light-emitting golf ball is provided. The light-emitting golf ball is characterized in that hemispherical first hollow portions extend from the surface toward the center of a core, second hollow portions having a diameter less than that of the first hollow portions extend from bottom zones of the first hollow portions toward the center of the core, narrow holes extend through the core from the second hollow portions to portions of the core that are opposed to the second hollow portions, a ball body includes a transparent cover layer extending over the core surface, chemical light-emitting bodies include sealed vessels made of a flexible transparent material, the sealed vessels have cylindrical portions and round light-emitting portions having a diameter greater than that of the cylindrical portions, the cylindrical portions are tightly fit in the second hollow portions, and the light-emitting portions are fit in the first hollow portions. The light-emitting golf ball has a brightness greater than that of conventional light-emitting golf balls and therefore can be visually identified from a distance. The light-emitting golf ball can be used many times by replacing the chemical light-emitting bodies with other ones. The balance of the ball is well maintained and therefore the flying performance thereof is not deteriorated.

The invention discloses tracking flying control system and method of a six-rotor unmanned helicopter. The six-rotor unmanned helicopter of the six-rotor unmanned helicopter comprises an onboard part and a ground station control part; the onboard part comprises a six-rotor flying platform and a flying controller; the ground station control part comprises a measuring control terminal with the wireless transmission function. The system has an automatic control mode and a manual control mode and has the characteristics of being small in size and light in weight. The invention further discloses a control method of the six-rotor unmanned helicopter of the six-rotor unmanned helicopter. The method is that the control output is calculated by the closed-loop control algorithm to control an actuating mechanism to work. With the adoption of the method, the indoor tracking flying of the six-rotor unmanned helicopter is achieved, and the applicable scope of the multi-rotor unmanned helicopter is expanded; the social benefit and economic benefit are increased.

A protector for the leading edge of a rotor blade to provide enhanced erosion protection thereof. In an embodiment, the protector includes an energy absorption member attached to the rotor blade by a first adhesive bond layer and an erosion resistant member attached to the energy absorption member by a second adhesive bond layer. The erosion resistant member is operative to protect the leading edge of the rotor blade from erosion due to impacts from particulate matter, such as sand and rain. The energy absorption member is operative to absorb and disburse energy from impacts to the erosion protection member so that forces from the impacts are diminished or not transferred to the rotor blade. In another embodiment, the erosion resistant member is coated with a diamond film. As the diamond film is harder than sand, excellent resistance to wear from particulate matter and impacts rain is obtained. Other advantages provided by use of the diamond film include: 1) an ultra-smooth surface that reduces drag on the rotor blade whereby flight performance may be improved, and 2) by being ultra-smooth and chemically inert de-icing equipment may not be needed.

The invention provides a multi-piece solid golf ball having a solid core, at least one intermediate layer and a cover. The core has a hardness which gradually increases from a core center to a core surface, with the hardness difference in JIS-C hardness units between the core center and the core surface being at least 15 and, letting (I) be the average value for the cross-sectional hardness at a position 15 mm from the core center and the cross-sectional hardness at the core center and letting (II) be the cross-sectional hardness at a position 7.5 mm from the core center, the hardness difference (I)-(II) in JIS-C hardness units being not more than ±2. The intermediate layer has a material hardness and the core has a surface hardness which together satisfy the condition (JIS-C hardness of intermediate layer material)−(JIS-C hardness of core surface)>0. A sphere composed of the core encased by the intermediate layer has an initial velocity and the core has an initial velocity which together satisfy the condition (initial velocity of sphere composed of core encased by intermediate layer)−(initial velocity of core)≧0. The sphere composed of the core encased by the intermediate layer has a deflection and the core has a deflection which together satisfy the condition 0.80≦(deflection of sphere composed of core encased by intermediate layer)/(deflection of core). The cover is formed primarily of polyurethane, and the cover material has a Shore D hardness and the intermediate layer material has a Shore D hardness which together satisfy the condition (Shore D hardness of cover material)−(Shore D hardness of intermediate layer material)≦0. The golf ball of the invention has an excellent flight performance and feel, a good durability to repeated impact, and an excellent scuff resistance.

A three-piece solid golf ball has excellent flight performance when hit by a driver or a long or a middle iron, and good spin performance when hit by a short iron or approach-shot. The three-piece solid golf ball has a core with a center and intermediate layer on the center; a cover on the core, the center with diameter 29 to 38 mm, hardness difference in JIS-C hardness at any point between its center to surface not more than 7, specific gravity lower than the intermediate layer, the surface hardness in JIS-C hardness of the intermediate layer being higher than the hardness determined at any point in the center; the difference between surface hardness of intermediate layer and hardness at any point in center being within 3° to 20° JIS-C, and cover having a Shore D hardness of less than 60.

Tilt-rotor aircraft experience increased efficiency and fuel economy by including wing extensions outboard of the tilting nacelles. Stall and buffeting during conversion from rotor-born hover to wing-born forward flight are reduced to an acceptable level using wide chord flaps deflected upwards by at least 15-20°, preferably in combination with leading edge slats. The outboard wing or wing portion is preferably has a span at least 25-40% of a span of the inboard section, and a total surface area at least 10-20% the total surface area of the corresponding inboard section.

The present invention provides a solid golf ball comprising a hot-molded product of a rubber composition comprising (a) 100 parts by weight of a polybutadiene synthesized using a rare-earth catalyst and having a cis-1,4 content of at least 60% and a 1,2 vinyl content of at most 2%, having a viscosity η at 25° C. as a 5 wt % solution in toluene of up to 600 mPa·s, and having Mooney viscosity (ML₁₊₄ (100° C.)) of more than 30, (b) 0.01 to 0.5 parts by weight of a sulfur, (c) 10 to 60 parts by weight of an unsaturated carboxylic acid and/or a metal salt thereof, (d) 0.1 to 5 parts by weight of an organosulfur compound, (e) 5 to 80 parts by weight of an inorganic filler, and (f) 0.1 to 5 parts by weight of an organic peroxide, wherein the hot-molded product has a difference in JIS-C hardness between the center and surface thereof of more than 20 and up to 40. The solid golf balls of the invention have a soft feel upon impact and excellent rebound characteristics. Moreover, the solid golf balls are improved in flight performance by making its spin rate reduced when shot with a driver.

The invention relates to a multi-vehicle working air line planning method and system of plant protection unmanned aerial vehicles and a spraying working method and system of the plant protection unmanned aerial vehicles. The planning method comprises the steps that a snake-shaped air line of the plant protection unmanned aerial vehicles during farmland spraying working is planned according to farmland coordinate parameters; the unmanned aerial vehicles are ranked according to the take-off sequence, and the spaying cut-off points of the unmanned aerial vehicles in the snake-shaped air line are calculated according to the sequence and the spraying flow and flying speed of each unmanned aerial vehicle; the starting point and cut-off point of each unmanned aerial vehicle are sent to the corresponding unmanned aerial vehicle to set the flight line, and the spraying cut-off point of the former unmanned aerial vehicle serves as the spraying starting point of the next unmanned aerial vehicle entering the air line. The errors of the planned air line are small, the flight effect of the unmanned aerial vehicles is good, multi-vehicle collaborative working can be achieved, the intelligent degree of spraying working is high, and the working efficiency of the unmanned aerial vehicles is improved.

Devices, systems and methods are disclosed which relate to providing wing designs with payload integration capabilities on existing modularly assembled unmanned aerial vehicles (UAVs). Exemplary embodiments of the present invention present a novel technique of adding payloads to existing UAVs while improving flight performance over existing techniques by maintaining a similar overall weight with improved aerodynamic properties. The technique includes using a reinforced foam core center wing with a fiberglass epoxy skin. A lightweight payload canopy cover integrates onto the center wing as an agnostic enclosure for payloads. The payload canopy cover may contain venting holes for the cooling of electronic payloads. The systems may also include common devices such as antennas, GPS, and batteries for use with a wide range of payloads.

The invention provides an unmanned aerial vehicle (UAV) trajectory smoothing method based on Bessel curve transition, comprising the following steps: constructing a Bessel transition function according to known linear route segments, and quickly establishing flight trajectory geometrical characteristics satisfying curvature continuity; with the length of the linear route segments and the allowed maximum trajectory smoothing error as constraints, establishing and solving an optimization problem of the smoothing transition length of each Bessel curve; determining maximum speed, acceleration and jerk constraints, and determining the maximum flight speed of transition segments based on the nature of the Bessel function; performing S-shaped motion planning for all linear segments, and determining the acceleration and deceleration time of each linear segment; iteratively searching and planning the flight speed of each segment to ensure the kinematic compatibility; and performing real-time interpolation to complete flight path generation. The flight performance of UAV can be improved greatly under the premise of guaranteeing the calculation efficiency.

The invention discloses an unmanned aerial vehicle flight time optimal real-time trajectory optimization method capable of ensuring convergence, and belongs to the field of trajectory optimization. According to the method, an unmanned aerial vehicle kinematics model is established under the consideration of gravity action, speed and acceleration factors, and a three-dimensional dimensionless motion equation is established. Constraint conditions of speed and control quantity are established according to specific requirements of obstacle avoidance flight of the unmanned aerial vehicle, and the minimum time is selected as an optimization target to establish an optimal control problem P0 of flight path planning of the unmanned aerial vehicle. Nonlinear dynamics in the problem P0 is transformedinto linear dynamics to obtain a fixed initial and end time trajectory optimization problem P1; and the P1 problem is relaxed into an approximate convex optimization problem P2 through convex relaxation, so that the robustness and robustness of real-time solving of the unmanned aerial vehicle are improved. And the problem P2 is discretized to form a second-order cone programming problem P3, and asecond-order cone programming problem P3 is solved iteratively for finite times to obtain an optimal solution, namely the optimal flight time trajectory of the unmanned aerial vehicle. The task response capability of the unmanned aerial vehicle can be further improved.

The invention discloses an estimation method of an atmosphere angle of attack and an angle of sideslip in a high-angle-of-attack flight status. Under the premise that the structure of an aircraft is not changed and additional measuring devices and hardware devices are not added, the parameters output by the existing onboard strapdown inertial navigation system, a GPS (Global Position System) system, a flight control system and a fuel measuring system are fully used for resolving the angular acceleration, the rotational inertia, the product of inertia, the coefficient of a moment equation set and the total mass of the aircraft; based on a flight dynamics model, by establishing an extended Kalman filter, and integrating the processes of resolving the flight dynamics model and the status estimation together, accurate estimation of the current angle of attack, the angle of sideslip and the true airspeed is realized, and then the current air speed and the change rate of the air speed are resolved and input into the extended Kalman filter as the feedback information so as to finish the real-time accurate estimation of the angle of attack and the angle of sideslip of next time; the real-time accurate estimation of the angle of attack and the angle of sideslip is realized by a recursive resolving mode, measurement range and measurement precision of an atmosphere data system are improved, and adaptability to complex flight environment is also improved.